Retention feature for soft interface connection

ABSTRACT

A retention feature configured to provide interference between a threaded connection of a Luer access device and a separate device, wherein the Luer access device further comprises a septum that provides a soft interfaced between the two threadedly connected devices. The retention features of the instant invention are designed to provide the user with a tactile sensation of a tightening threaded connection, despite a soft interface between the interconnected devices. The retention features of the instant invention further prevent “spring back” and unintentional disengagement of the interconnected devices.

BACKGROUND OF THE INVENTION

The present invention relates generally to features and devices toimprove a threaded connection between two or more devices, wherein asoft interface is provided between the devices. In particular, thepresent invention relates to a retention feature that is configured tointerfere with a threaded connection, wherein the presence of theretention feature provides increased frictional force between thethreads of the threaded devices, thereby increasing the force requiredto disengage the devices and providing the user with tactile feedbackwhich indicates a status of the threaded connection.

Traditional threaded conical or Luer fittings utilize a 6% Luer taper onopposing surface of the connectors to be threadedly connected. As thethreads of the connectors are rotated relative to each other, the maleand female conical surface are driven and wedged together, therebyforming a secure and fluid-tight connection. Most often this type oftraditional connection is best accomplished when the male and femaleconical surfaces are either non-compliant or equally compliant, suchthat the opposing surfaces are able to achieve a secure fit. Whentightening these surfaces, friction between the male and female conicalsurfaces provides resistance to disengaging the devices and furtherprovides the user with a tactile sensation or feedback which indicates acomplete and secure connection has been achieved.

With reference to FIGS. 1 and 2, a depiction of a PRIOR ART vascularaccess device 10 is shown. Generally, a vascular access device 10 isused to introduce a substance via a catheter 12 across the skin 14 andinto a blood vessel 16 of a patient 18. The vascular access device 10typically includes a body 20 with a lumen or opening 34 and a softseptum 22 placed within the opening. The vascular access device 10,including the body 20 and the septum 22, may comprise various structuraland design modifications, as are presently known in the art.

In some examples, soft septum 22 has a slit 24 through which a separateextravascular device 26, such as a syringe, may introduce a substanceinto the vascular access device 10. A syringe is one exemplary separatedevice 26. Other suitable known extravascular devices may includeadditional vascular access devices, IV administration sets, a male Lueradapter, or other common or yet to be developed medical devices.

A vascular access device 10 may be combined with various otherintravenous components to form a larger extravascular system 28. As partof operating the extravascular system 28, a tip 30 of the separatedevice 26 may be inserted into the vascular access device 10 throughslit 24 of soft septum 22. The tip 30 penetrates the device 10separating at least portions of the two opposing slit surfaces of septum22. Septum 22 and slit 24 may be configured to seal, or at leastsubstantially seal, around tip 30 as it is inserted into the vascularaccess device 10. Accordingly, the surfaces near the slit ends may notbe separated until the tip 30 is sufficiently inserted into vascularaccess device 10. The tip 30 serves to open the slit 24 to allow fluidto pass through the device 10, into the catheter 12, and out the end 32of the catheter when the device is in use.

Generally, the body 20 of vascular access device 10, and separate device26 comprises a rigid or semi-rigid polymer material, such aspolycarbonate or polypropylene. Septum 22 generally comprises a soft,pliable, resilient material, such as silicon or polytetrafluoroethylene.Thus, when separate device 26 is inserted through slit 24 of septum 22,septum 22 provides a soft, pliable barrier between the rigid orsemi-rigid materials of separate device 26 and body 20. Although theinterface between septum 22 and separate device 26 is secure andfluid-tight, the non-compliant material of separate device 26 andcompliant material of septum 22 may reduce the security of theconnection and reduces the desired tactile feedback to the user that isexperienced with traditional Luer connections. Thus, the user may beunsure of the security of the connection which may result in theconnection being over-tightened or unnecessarily examined.

In some instances, the act of threadedly coupling separate device 26 tobody 20 causes an exposed portion of septum 22 to become pinched betweenseparate device 26 and body 20. The resilient properties of septum 22cause a “spring back” effect between the two threaded components,wherein separate device 26 may become partially unthreaded from body 20following tightening. This “spring back” effect may further reduce thesecurity of the connection and provide a dissatisfying tactile sensationto the user, wherein the soft interface of septum 22 prevents the userfrom sensing a progression of tightening between separate device 26 andbody 20. The user therefore may lack confidence in the connection andmay attempt to over-tighten the components, as discussed previously.

Thus, while techniques currently exist that are used for interconnectingthreaded devices, challenges still exist. Accordingly, it would be animprovement in the art to augment or even replace current techniqueswith other techniques.

BRIEF SUMMARY OF THE INVENTION

The present invention relates generally to features and devices toimprove a threaded connection between two or more devices, wherein asoft interface is provided between the devices. In particular, thepresent invention relates to a retention feature that is configured tointerfere with a threaded connection, wherein the presence of theretention feature provides increased frictional force between thethreads of the threaded devices, thereby increasing the security of theconnection and providing the user with tactile feedback which indicatesa status of the threaded connection. In some instances, the retentionfeature provides the user with a tactile sensation that indicates thatthe threaded connection is progressively or gradually tightening.

In some implementations, a retention feature is provided to prevent“spring back” from occurring due to a soft interface between thethreadedly coupled devices. For example, a retention feature may beprovided which increases frictional force between the threads of thedevice and the retention feature, thereby interlocking the threadedsurfaces. In other instances, a retention feature is provided comprisinga non-compliant material, wherein the compliant material of one or moreof the threadedly interconnected devices is temporarily deformed by thepresence of the retention feature, thereby increasing the frictionalforce between the sets of engaged threads. Further, in some instances aretention feature is provided comprising a compliant material, whereinthe non-compliant material of one or more of the threadedlyinterconnected devices temporarily deforms the retention feature whencontacted, thereby increasing the frictional force between the retentiondevice and the threads. The act of deforming the retention feature mayalso increase the friction force between the set of interconnectedthreads.

Some implementations of the instant invention provide a Luer accessdevice comprising a body having an outer surface. The Luer access devicefurther includes an opening formed in the outer surface and configuredto receive a separate device, such as a needleless connector. The Lueraccess device further includes a soft septum disposed in the opening andhaving a slit for receiving the separate device. The Luer access devicefurther includes a set of threads positioned on the outer surface of thedevice and in proximity to the opening of the device. Further still, theLuer access device comprises a retention feature that is disposed on thebody at a position adjacent the set of threads, and positioned tocontact a portion of a complementary set of threads of the separatedevice when threadedly coupled to the set of threads of the Luer accessdevice. When contact is made between the complementary threads and theretention feature, tactile feedback is provided to a user whichindicates a tightened connection between the Luer access device and theseparate device, and an increased force necessary to disconnect thedevices is produced to prevent unintentional disengagement of theseparate device from the Luer access device.

In some instances, the retention feature comprises a protrusion. Theretention feature may be positioned at any location on the Luer accessdevice. In some instances, the retention feature is positioned betweenan upper thread and a lower thread of the Luer access device's set ofthreads. In other instances, the retention feature comprises a first endthat abuts the lower thread, and further comprises a second end thatabuts the upper thread. The retention feature may further comprise anaxial taper, wherein a surface of the retention feature tapers outwardlyfrom a base of the feature to a top of the feature. For example, in someinstances the second end of the retention feature comprises a protrusionheight that is greater than a protrusion height of the first end, suchthat the retention feature tapers inwardly from the second end to thefirst end.

The retention feature may further comprise a ramped configuration,wherein the second end of the retention feature comprises a protrusionheight that is greater than a protrusion height of the first end, suchthat the ramped protrusion tapers inwardly from the second end to thefirst end. The retention feature may further comprise a forward leadingramped surface and a rearward or trailing ramped surface, wherein theramped surfaces taper outwardly from the body of the Luer access deviceto an apex of the retention feature. In some instances, the apex issymmetrical. In other instance, the apex is asymmetrical wherein theapex comprises a first width that is greater than a second width toprovide an axial taper that forms an interface with the forward rampedsurface. Further, some implementations of the instant invention providea retention feature having a forward ramped surface comprising a firstangle of incline, and a rearward ramped surface comprising a secondangle of incline, wherein the second angle of incline is greater thanthe first angle of incline.

The present invention further provides a method for manufacturing a Lueraccess device, the method including steps for: 1) providing a bodyhaving an outer surface; 2) forming an opening in the outer surface ofthe body, the opening being configured to receive a separate device,such as a needleless connector; 3) disposing a soft septum into theopening, the soft septum having a slit for receiving the needlelessconnector; 4) providing a set of threads of the outer surface andpositioned proximate to the opening, a portion of the body beingadjacent the set of threads; and 5) disposing a retention feature on theportion of the body adjacent the set of threads, wherein the retentionfeature is positioned to contact a portion of a complimentary set ofthreads on the needleless connector when threadedly coupled to the setof threads and provide both resistance to disconnection and provide atactile feedback to a user of a tightening connection between the Lueraccess device and the needleless connector.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

In order that the manner in which the above-recited and other featuresand advantages of the invention are obtained will be readily understood,a more particular description of the invention briefly described abovewill be rendered by reference to specific embodiments thereof which areillustrated in the appended drawings. These drawings depict only typicalembodiments of the invention and are not therefore to be considered tolimit the scope of the invention.

FIG. 1 show a perspective view of a PRIOR ART Luer access device as partof an intravenous system.

FIG. 2 shows a cross-section view of a PRIOR ART separate device coupledto a PRIOR ART Luer access device as part of an intravenous system.

FIG. 3, shown in parts A-G, shows various views of a Luer access devicehaving a retention feature in accordance with a representativeembodiment of the present invention.

FIG. 4, shown in parts A-C, shows various views of a Luer access devicehaving a tapered retention feature in accordance with a representativeembodiment of the present invention.

FIG. 5, shown in parts A and B, shows a cross section view of thetapered retention feature of FIG. 4, and demonstrates the operation oftightening a threaded connection between the Luer access device and aseparate device in accordance with a representative embodiment of thepresent invention.

FIG. 6, shown in parts A-C, shows various views of a Luer access devicehaving an asymmetrical narrow bump retention feature in accordance witha representative embodiment of the present invention.

FIG. 7, shown in parts A-C, shows various views of a Luer access devicehaving an asymmetrical wide bump retention feature with an axial taperin accordance with a representative embodiment of the present invention.

FIG. 8, shown in parts A-C, shows various views of a Luer access devicehaving a barb retention feature in accordance with a representativeembodiment of the present invention.

FIG. 9 shows a perspective view of a Luer access device having retentionfeature forming a portion of a thread in accordance with arepresentative embodiment of the present invention.

FIG. 10 shows a perspective view of a Luer access device having aretention feature forming a portion of a separate thread in accordancewith a representative embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

It will be readily understood that the components of the presentdisclosure, as generally described and illustrated in the figuresherein, could be arranged and designed in a wide variety of differentconfigurations. Thus, the following more detailed description, asrepresented in the figures, is not intended to limit the scope of thedisclosure, but is merely a representative of exemplary combinations ofthe components.

As used herein, the term “needleless connector” is used to denote amedical coupler which is used as part of an intravenous assembly. Insome instances, a needleless connector comprises a Luer adapter. Inother instances, a needleless connector comprises a PRN connector. Anexample of a needleless connector is the Q-Syte™ luer access port fromBecton, Dickinson. Further, in some instances a needleless connectorcomprises a port or valve of a section of intravenous tubing or aconnector thereof. One having skill in the art will appreciate that thesystems and methods of the present invention may be adapted for use withvarious other types of connectors and other devices for which automateddisinfection is desirable.

Referring now to FIG. 3, a Luer access device 100 in accordance to arepresentative embodiment of the present invention is shown. Luer accessdevice 100 may comprise any general structure or design that ispresently known in the art. For example, in some instances Luer accessdevice 100 comprises cap structure as shown in FIG. 3A. Luer accessdevice 100 may alternatively comprise a male Luer device, as shown incross-section in FIG. 3B. Luer access device 100 may further comprise anaccess port structure that is part of an intravenous connector.

Luer access device 100 comprises a body 120 made from a rigid orsemi-rigid material having an opening 134 into which is seated a softseptum 122. Body 120 further comprises a set of threads 140 that ispositioned on the outer surface of body 120 and in proximity to opening134. Threads 140 are provided to facilitate a threaded connectionbetween Luer access device 100 and a separate device 26, such as asyringe, a Luer adapter, a cap, or a section of intravenous tubing. Insome instance, threads 140 comprises a plurality of partial threads thatoccupy a portion of the outer surface of body 120, wherein the partialthreads each have a thread length that is less than the circumference ofthe outer surface on which the threads are positioned.

Luer access device 100 further comprises a retention feature 150 that ispositioned on body 120 adjacent the set of threads 140. In general,retention feature 150 is positioned on body 120 such that retentionfeature 150 will contact a set of complementary threads on the separatedevice 26 when the separate device 26 is threadedly coupled to Lueraccess device 100 via threads 140. Accordingly, the specific location ofretention feature 150 may vary and still accomplish its intendedpurpose.

For example, in some instances retention feature 150 is positioned belowthread 140 at a position near the middle or end of the thread, as shownin FIGS. 3A and 3B. As thus configured, the complementary threads ofseparate device 26 are able to engage threads 140 prior to contactingretention feature 150. As separate device 26 is further threaded ontothreads 140, the complementary threads of separate device 26 contactretention feature 150 thereby providing a tactile sensation to the userof a tightening connection between the two components. Contact betweenthe complementary set of threads and retention feature 150 furtherprovided increased friction between the threaded components, therebyovercoming the “spring back” effect caused by soft septum 122.

Retention feature 150 may comprise any shape, configuration, texture orother feature that is compatible with the teachings of the presentinvention. In some instances, retention feature 150 comprises aprotrusion that provides an obstacle in the pathway for a set ofcomplementary threads that is intended to threadedly engage threads 140.

For example, retention feature 150 may be positioned in proximity tothreads 140 so as to be in the pathway of a set of complementary threadsof a separate extravascular device. As separate device 26 is initiallythreaded onto threads 140 of Luer access device 100, a probe 138 portionof separate device 26 pierces septum 122, as shown in FIG. 3C. In someinstances, as probe 138 is advanced through septum 122, complementarythreads 36 do not immediately make contact with retention feature 150.Rather, threads 140 and complementary threads 36 are permitted to freelyand fluidly engage. However, upon further engagement betweencomplementary threads 36 and threads 140, complementary threads 36contact retention feature 150 as separate device 26 and Luer accessdevice 100 near complete, threaded engagement, as shown in FIG. 3D.

The contact and interaction between complementary threads 36 andretention feature 150 provides a change in the mechanics of the threadedconnection. In some instances, this change requires increased rotationaltorque by the user to complete the threaded connection between the twocomponents. In other instances, this change further provides increasedfriction between the two components, which can be felt by the user asthe connection is tightened. Accordingly, retention feature 150overcomes the “spring back” effect of soft septum 122, improvingsecurity of the connection while simultaneously provided the user with adesirable tactile feedback that confirms tightening of the connection.

In some instances, the complementary threads of separate device 26comprises a compliant material that is temporarily or permanentlydeformed when the complementary threads of the device 26 contactretention feature 150, as shown in FIG. 3E. The contact between thecomplementary threads and retention device 150 may temporarily orpermanently misshape the inner diameter of separate device 26, or theshape of complementary threads, thereby increasing the rotational forcerequired to continue coupling separate device 26 and Luer access device100.

Conversely, in some instances retention feature 150 comprises acompliant material that is temporarily or permanently deformed when thenoncompliant complementary threads of device 26 contact retentionfeature 150, as shown in FIG. 3F. The complementary threads of device 26cut into retention feature 150, thereby increasing friction between thetwo components.

Further still, in some instances body 120 comprises a compliant materialthat is temporarily deformed when contact is made between separatedevice 26 and retention feature 150, as shown in FIG. 3G. For example,in some instances a noncompliant interface between the complementarythreads 36 and retention feature 150 displaces or deflects complementarythreads 36 outwardly, thereby increasing the rotational torque requiredto complete the threaded connection between Luer access device 100 andseparate device 26.

Referring now to FIGS. 4A-4C, Luer access device 100 may furthercomprise a tapered retention feature 250. In some instances, Luer accessdevice 100 comprises a single tapered retention feature 250 that ispositioned beneath a set of threads 140 of body 120, as shown in FIGS.4A and 4B. In other embodiments, Luer access device 100 comprises one ormore tapered retention features 250 that are interposedly positionedbetween an upper thread 140 a and a lower thread 140 b on body 120, asshown in FIG. 4C. Retention feature 250 tapers inwardly from upperthread 140 a to lower thread 140 b, such that retention feature 250comprises an upper thickness that tapers to a lower thickness, whereinthe lower thickness is less than the upper thickness.

Referring now to FIGS. 5A and 5B, various cross-section views areprovided which demonstrate the interaction between complementary threads36 of separate device 26 and tapered retention feature 250. As separatedevice 26 is threadedly coupled to Luer access device 100, the undersideof complementary threads 36 is initially supported by a top surface ofthreads 140, as shown in FIG. 5A. Upon further coupling or threading ofthe devices, contact is made between the terminal end 37 of separatedevice 26 and body 120 of Luer access device 100, thereby preventingfurther insertion of probe 138 through septum 122, as shown in FIG. 5B.In at least some embodiments, contact between complementary threads 36and tapered retention feature 250 occurs at or before the initiation ofcontact between terminal end 37 and body 120.

Upon further rotation of separate device 26, complementary threads 36are rotated with respect to the fixed position of body 120 and threads140. The pitch of complementary threads 36 causes the rotatingcomplementary threads 36 to travel upwardly across retention feature250, such that a top surface of complementary threads 36 contacts abottom surface of upper threads 140 a. As complementary threads 36travels across retention feature 250, the outward taper of retentionfeature 250 increases resistance between complementary threads 36 andretention feature 250. This increased resistance provides a desiredtactile sensation to the user which indicates that the connectionbetween the devices is progressively tightening. When the top surface ofcomplementary threads 36 is fully seated against the bottom surface ofthreads 140, and terminal end 37 is contacting body 120, the connectionbetween the devices 100 and 26 is complete and the user is no longerable to further rotate and/or tighten the connection. The interactionbetween complementary threads 36 and retention device 250 maintains thetightened connection, thereby preventing any “spring back” effect.

The present invention may comprise any number of retention features,having any variety of size, shape and features in harmony with theteachings herein. For example, with reference to FIGS. 6A-6C, someimplementations of the present invention comprise a retention feature350 comprising an asymmetric bump having various axial ramps to assistin tightening and loosening the connection between Luer access device100 and separate device 26.

In some instances, retention feature 350 comprises a forward rampedsurface 352 having a shallow, inclined pitch. The force required to passcomplementary threads 36 over retention feature 350 increases graduallyas complementary threads 36 travel over the inclined ramped surface 352.Retention feature 350 further comprises rearward ramped surface 354which is opposite forward ramped surface 352 and includes a steep,declined pitch.

In some instances, complementary threads 36 comprise a compliantmaterial that temporarily deforms when contacted by retention feature350. As such, when threadedly coupling complementary threads 36 tothreads 140, a portion of complementary threads 36 in contact withretention feature 350 gradually and temporarily deforms as the threads36 travel up forward ramped surface 352 and over the apex 356 ofretention feature 350. As the portion of complementary threads 36 passesover apex 356 and past rearward ramped surface 354, the threads 36 arerestored to their original form. Thus, the sections of complementarythreads 36 not in contact with retention feature 350 are undeformed,while those sections of complementary threads 36 in contact withretention feature 350 are deformed, as shown in FIG. 6C.

The interface between complementary threads 36 and the steeper pitch ofrearward ramped surface 354 requires increased torque for disengaging orunthreading complementary threads 36 from threads 140, as compared tothe torque required to threadedly engage threads 36 and 140 based on theshallower pitch of forward ramped surface 354. This feature preventsunintentional disengagement of separate device 26 from Luer accessdevice 100. Further, the steeper pitch and shorter length of rearwardramped surface 354 allows quick disengagement of complementary threads36 from retention feature 350 once the required torque has been appliedand the interface between complementary threads 36 and rearward rampedsurface 354 has been released.

In some instances, Luer access device 100 further comprises a retentionfeature 450 having an asymmetrical wide bump 456 comprising an axialtaper, wherein the wide bump 456 further comprises a shallow forwardramp 452 and a steep rearward ramp 454, as shown in FIGS. 7A-7C. Forwardand rearward ramps 452 and 454 provide benefits similar to thosediscussed in connection with retention feature 350, above. Wide bump 456is equivalent to apex 356 of retention feature 350, however theincreased width of wide bump 456 increases the interface betweenretention feature 450 complementary threads 36. As such, the period ofresistance between Luer access device 100 and separate device 26 isincreased. The increased width of wide bump 456 further increases thelength or amount of complementary threads 36 that are deformed byretention feature 450, thereby requiring additional torque to threadedlyengage and/or disengage the interconnected devices.

Wide bump 456 further comprises an axial taper, similar to the taper ofretention feature 250, shown and discussed above in connection withFIGS. 4A-5B. Thus, as separate device 26 is threaded onto Luer accessdevice 100, complementary threads 36 travel upwardly on the axial taperof wide bump 456, thereby increasing the resistance betweencomplementary threads 36 and retention feature 450. Complementarythreads 36 are maximally engaged with threads 140 when an upper threadsurface of complementary threads 36 forms an interface with a lowerthread surface of threads 140, thereby preventing further rotation ofseparate device 26. In this position, complementary threads 140 arepositioned on wide bump 456 at the maximum width of the axial taper,thereby maximizing the interference between retention feature 450 andcomplementary threads 36.

Referring now to FIGS. 8A-8C, some embodiments of the instant inventionfurther include a retention feature 550 comprising a one-way barb. Insome embodiments, retention feature 550 comprises a flexible, resilientmaterial and is positioned in the pathway of complementary threads 36,such that complementary threads 36 contact and temporarily displaceretention feature 550, as shown in FIG. 8C. In some embodiments,retention feature 550 comprises a wide base and a narrower tip, suchthat the shear strength of retention feature 550 is less at the tip andgreater at the base. Thus, less shear force is required to displace thetip of retention feature 550 than is required to displace the base. Assuch, the user is provided with a tactile sensation of a graduallytightening connection. In some instances, retention feature 550comprises tapered sidewalls, such that the shear strength of retentionfeature 550 progresses linearly from the feature's tip to the base. Inother instances, retention feature 550 comprises sidewalls having aconfiguration to achieve a non-linear progression of shear strength fromthe tip to the base.

The resilient nature of retention feature 550 applies an outward forceon complementary threads 36 when displaced. This outward force providesa tactile sensation to the user which indicates that the threadedconnection is tightening. The outward force further increases the torquerequired to continue advancing the threaded connection. Once fullyengaged, the outward force prevents unintentional disengagement of thethreaded devices.

When unthreading the devices, the outward force applied by retentionfeature 550 requires increased torque to overcome the frictional forcebetween complementary threads 36 and retention feature 550. Thefrictional force between complementary threads 36 and retention feature550 gradually decreases as the devices are unthreaded due to the taperedconfiguration of complementary threads 36 and the resilient nature ofretention feature 550. At the point in which complementary thread 36 nolonger contacts retention feature 550, all frictional force betweenthreads 36 and feature 550 ceases and the amount of torque required tounthread the devices decreases.

Referring now to FIG. 9, in some embodiments a retention feature 650 isprovided as part of threads 140. In this configuration, retentionfeature 650 interacts with the surface of separate device 26 that isinterposed between, or adjacent to complementary threads 36, as opposedto directly interacting with complementary threads 36. For example,retention feature 650 may be designed to engage a major diameter ofcomplementary threads 36, wherein the previous retention featureembodiments are configured to engage the minor diameter of complementarythreads 36.

Retention feature 650 may comprise any of the features or elements ofthe previously discussed retention features. For example, in someinstances retention feature 650 comprises a forward ramped surface 652and a rearward ramped surface 654. Retention feature 650 may furthercomprise a wide bump surface. In some instances, a Luer access device isprovided which comprises two or more retention features, wherein a firstretention feature is configured to directly interact with a set ofcomplementary threads, and a second retention feature is configured tointeract with a surface of a separate device that is interposed between,or adjacent to the complementary threads.

In some instances, Luer access device 100 includes a retention feature750 that comprises a portion of a separate thread 140 a. Thus, a gap 141is provided between threads 140 and separate thread 140 a. Retentionfeature 750 may include any feature or combination of features discussedabove in connection with any of the other retention features. In someinstances, retention feature 750 comprises wide bump 756 that is taperedradially from the forward ramped surface 752 to the rearward rampedsurface 754. Thus, the frictional force between retention feature 750and the major diameter of complementary threads 36 increases graduallyas contact between wide bump 756 and complementary threads is advances.

The present invention may be embodied in other specific forms withoutdeparting from its structures, methods, or other essentialcharacteristics as broadly described herein and claimed hereinafter.Thus, the described embodiments are to be considered in all respectsonly as illustrative, and not restrictive. The scope of the inventionis, therefore, indicated by the appended claims, rather than by theforegoing description. All changes that come within the meaning andrange of equivalency of the claims are to be embraced within theirscope.

1. A Luer access device, comprising: a body having an outer surface; anopening formed in the outer surface and configured to receive aneedleless connector; a soft septum disposed in the opening and having aslit for receiving the needleless connector; a set of threads on theouter surface and positioned proximate to the opening, a portion of thebody being adjacent the set of threads; and a retention feature disposedon the portion of the body adjacent the set of threads, wherein theretention feature is positioned to contact a portion of a complimentaryset of threads on the needleless connector when threadedly coupled tothe set of threads and provide increased resistance to unintentionaldisengagement of the threaded devices and a tactile feedback to a userof a tightened connection between the Luer access device and theneedleless connector.
 2. The device of claim 1, wherein the retentionfeature comprises a protrusion.
 3. The device of claim 2, wherein theset of threads comprises an upper thread and a lower thread, and theportion of the body adjacent the set of threads is interposed betweenthe upper and lower threads.
 4. The device of claim 3, wherein theprotrusion comprises a first end that abuts the lower thread and asecond end that abuts the upper thread.
 5. The device of claim 4,wherein the second end comprises a protrusion height that is greaterthan a protrusion height of the first end such that the protrusiontapers inwardly from the second end to the first end.
 6. The device ofclaim 4, wherein the second end comprises a protrusion height that isgreater than a protrusion height of the first end such that the rampedprotrusion tapers inwardly from the second end to the first end.
 7. Thedevice of claim 2, wherein the protrusion comprises a forward rampedsurface and a rearward ramped surface, the forward ramped surfacetapering outwardly from the portion of the body adjacent the set ofthreads to an apex of the protrusion.
 8. The device of claim 7, whereinthe apex is asymmetrical and comprises a first width that is greaterthan a second width to provide an axial taper that forms an interfacewith the forward ramped surface.
 9. The device of claim 7, wherein theforward ramped surface comprises a first angle of incline and therearward ramped surface comprises a second angle of incline, the secondangle of incline being greater than the first angle of incline.
 10. Thedevice of claim 9, wherein the first angle of incline provides a gradualincrease in torque required to threadedly couple the Luer access deviceto the needleless connector, and the second angle of incline provides aninitial resistance when loosening a threaded connection between the Lueraccess device and the needleless connector.
 11. The device of claim 1,wherein the retention feature comprises a barb.
 12. The device of claim1, wherein the barb is temporarily deformed when contacted by thecomplementary set of threads on the needleless connector.
 13. A Lueraccess device, comprising: a body having an outer surface; an openingformed in the outer surface and configured to receive a needlelessconnector; a soft septum disposed in the opening and having a slit forreceiving the needleless connector; a set of threads on the outersurface and positioned proximate to the opening; and a retention featuredisposed on a portion of the set of threads, wherein the retentionfeature is positioned to contact a portion of a complimentary set ofthreads on the needleless connector when threadedly coupled to the setof threads and provide increased resistance to unintentionaldisengagement of the threaded devices and a tactile feedback to a userof a tightened connection between the Luer access device and theneedleless connector.
 14. The device of claim 13, wherein the retentionfeature comprises a protrusion.
 15. The device of claim 14, wherein theprotrusion comprises a leading edge and a trailing edge, the leadingedge comprising a ramped surface that tapers outwardly from an outer rimsurface of the set of threads to an apex of the protrusion.
 16. Thedevice of claim 15, wherein the leading edge comprises a first angle ofincline and the trailing edge comprises a second angle of incline, thesecond angle of incline being greater than the first angle of incline.17. The device of claim 13, wherein the set of threads comprises a gapdividing the set of threads into a first section and a second section,wherein the retention feature is located on the second section.
 18. Thedevice of claim 13, wherein the set of threads comprises two or morethreads.
 19. A method for manufacturing a Luer access device, the methodcomprising: providing a body having an outer surface; forming an openingin the outer surface of the body, the opening be configured to receive aneedleless connector; disposing a soft septum into the opening, the softseptum having a slit for receiving the needleless connector; providing aset of threads on the outer surface and positioned proximate to theopening, a portion of the body being adjacent the set of threads; anddisposing a retention feature on the portion of the body adjacent theset of threads, wherein the retention feature is positioned to contact aportion of a complimentary set of threads on the needleless connectorwhen threadedly coupled to the set of threads and provide increasedresistance to unintentional disengagement of the threaded devices and atactile feedback to a user of a tightening connection between the Lueraccess device and the needleless connector.
 20. The method of claim 19,wherein the retention feature comprises a protrusion.